Harvard Physicists Calculate Lunar Water Cap at 10,000 Residents

Martin Elvis and Jonathan McDowell published a study in Frontiers in Space Technologies stating that lunar water reserves likely support sustainable settlements of only 10,000 people.

The researchers, affiliated with Harvard University and Durham University respectively, analyzed power and water requirements for large-scale lunar habitation. They concluded that while solar and nuclear energy could power one million residents, water availability remains the limiting factor.

Elvis noted that the estimated one billion tonnes of lunar water is likely an overestimation. He suggested the actual recoverable amount may be one per cent of that figure, which would reduce the lifespan of a million-person city from 100 years to one year.

The study assumes that 98 per cent of water is recycled, a rate currently achieved on the International Space Station. Without this level of efficiency, the timeline for resource depletion would shorten further.

McDowell stated that if future plans aim to cover the moon with cities, engineers must find methods to transport water to those locations. He emphasized that the findings are practical rather than discouraging, noting that understanding limits helps guide future efforts.

Gordon Osinski, a planetary geologist at Western University, cautioned that satellite measurements of lunar ice remain uncertain. He described the water as potentially resembling Arctic permafrost, with tiny ice crystals mixed into soil that are difficult to extract.

The analysis responds to recent claims by industry leaders. Elon Musk stated in February that SpaceX is building a self-growing city on the moon, a project he said could be completed in under 10 years. Jeff Bezos has claimed millions of people will live in space by 2045.